Already known is a method for hot rolling of bevel gears (cf. USSR Inventor's Certificate No. 275995, Cl. B 21 H 5/04, 1966), comprising infeeding a freely rotating gear rolling die with a synchronizing member into a work gear with a synchronizing member rotated by a power drive. First, the teeth of the synchronizing members are caused to mesh. The gear rolling die is thereby rotated by the work gear synchronizing member. Then the indexing forming the teeth on the work gear and the finish rolling of the teeth take place under the action of those teeth of the gear rolling die.
An apparatus for carrying out a method for hot rolling of bevel gears (cf. USSR Inventor's Certificate No. 275995, Cl. B 21 H 5/04, 1966), also is known to compare a bed, a work gear spindle having a work gear chucking means, a gear rolling die spindle having a gear rolling die secured thereto. The work gear spindle and the gear rolling die spindle are installed in the bed in an angular relationship with each other. Synchronizing members are provided on the end faces of the work gear spindle and gear rolling die spindle. The apparatus also comprises power drives for rotating the work gear spindle and for axially moving the gear rolling die spindle.
The above described method and apparatus for hot rolling of bevel gears according to the prior art involve bringing into a meshing relationship non-rotating teeth of a gear rolling die synchronizing member and the rotating teeth of a work gear synchronizing member which results in knocking and breakage of the teeth of the die and work gear synchronizing teeth. In addition, the accuracy and the quality of the rolled teeth of a gear are determined by the quality and the accuracy of the teeth of the synchronizing members of the gear rolling die and of the work gear rather than by the quality and the accuracy of the teeth of the gear rolling die. As a result, the accuracy and the quality of the rolled teeth of a gear are not high enough. Accordingly, the service life of the gear rolling die is short and amounts to only 2000-3000 rolled gears.
A method for hot rolling of bevel gears (cf. USSR Inventor's Certificate No. 753521, Cl. B 21 H 5/04, 1980), likewise is known to comprise infeeding a gear rolling die having a synchronizing member and rotated by an independent low-power drive into a work gear having a synchronizing member and rotated by a power drive. According to this method the teeth of the synchronizing members of the gear rolling die and of the work gear first are brought into a meshing relationship, and then the indexing tooth forming and finish rolling of the rolled teeth of the gear are performed under the action of the teeth of the gear rolling die.
An apparatus for carrying out a method for hot rolling of bevel gears (cf. USSR Inventor's Certificate No. 753521, Cl. B 21 H 5/04, 1980), is known to comprise a bed, a work gear spindle having a work gear chucking means and a work gear power drive. An axially movable gear rolling die spindle having a gear rolling die is installed in the bed at an angle to the work gear spindle. Synchronizing members are provided on the end faces of the work gear spindle and the gear rolling die spindle. A non-power drive for rotating the gear rolling die is provided on the gear rolling die spindle. The gear rolling die spindle is connected to the bed through an axial motion drive which comprises Euler levers and a hydraulic cylinder. In this method for hot gear rolling and in the apparatus for carrying out the method, the accuracy and quality of rolled gear teeth are determined by the accuracy and quality of synchronizing members of the spindles which act as power drive members during the indexing tooth forming on the work gear and finish rolling of rolled gear teeth, rather than by the accuracy and the quality of teeth of the gear rolling die. As a result, the accuracy and quality of rolled gear teeth are rather inadequate. Owing to differences between the teeth of the gear rolling die and of the synchronizing members of the gear rolling die and work gear spindle, the gear rolling die has a short service life which amounts to only 2000-3000 rolled gears.